Electric heater.



W. S. ANDREWS.

ELECTRIC HEATER.

APPLIOATION FILED JAN. 15, 1908.

910,479.` Patented Jan. 19, 1909.

INVENTUR @LL/'AM 5. NUHEI/Y www TTY

I/I/ITNE'SEES.' mm. g. 999. 999,

UNITED sTATEs PATENT OEEIOE.

WILLIAM `s/ANDREWS, or scIIENEoTADY, NEW YORK, AssIeNOn` To GENERAL ELECTRIC COMPANY, A CORPORATION or NEW Your.;L

Specicattrm o! Letters atent,

Patented Ian.. I9, 1909.

Application led. January 15, 190.18. Serial No. 410,920.

To all whom it may concern: v j

Be it known that I, WILLIAM S. ANDREWS, a citizen of the United States,residing at Schenectady, county of Schenectady, State of New York, have invented certain new and useful Improvements in Electric Heaters, of which the following is a specification. V

This invention relates to electric heating devices and has for itsobjcct the provision of a device ol' this character which is simple and durable in construction and efficient and reliable in operation, the arrangement being such that the unit may be readily replaced by an unskilled person.

In carrying out my invention I therefore construct a heater in three parts, a body ortion, a heating unit adapted to he hel in intimate thermal relation therewith, and a receptacle for supporting the heating unit. The heating unit is placed in the receptacle and the latter is thon secured to the body portion.

Other objects'or my invention will a pear in the course of the following speciiicatlon in which I have shown my invention embodied in concrete form ier pur oses oi illustration.

In the accom anying rawings illustrating my invention, .figure 1 is an elevation oi' a heating device provided with my improvement; l` ig. 2 is a sectional view ol the heating unit and terminal; Fig. 3 is a sectional view of the casing for the resistance conductor; and Fig. 4 is a plan viow'of the unit with the cover removed.

Referring to the drawings, 10 re rosents the body portion of the heater, Whic in this case is a `fluid container and may be of any desired shape. A receptacle 1.1 provided with supporting logs is adapted to lit over the bottorn oi the vessel 10 wliilc aliatheating unit 12 is arranged to be secured between the bottom 18 of the vessel and the bottom ol the receptacle. The receptacle and vessel are arranged to be secured together by means ol' a bayonet joint connection, lthis connection being merely a tapering slot 14 on opposite sides of the rece tacle engaged by correspondingly arrange pins 15.

The heating unit 12 consists lof telescoping casin s 16 and 17 circular in form and of shallow ilepth. The heating or resistance conductor 18 is formed in anysuitable Way, as for instance by a coiled WIre laid spiral y in the bottom of the casing 16,' the turns being separated by an insulating strip 19. The ends of this conductor are secured te the two terminals 20 and 21. These terminals project through the bottom of the casing 16 and are surrounded b or molded into an insulatinghblock'22. '1 e terminals are bent at a rig t angle within the block so as to project inea plane parallel with the bottom of the casin The heating element thus becomes a seit-contained unit havin the resistance conductor secured between t e casing 16 and the telesco ping cover 17 Within a thin sheet oi insulating material 23 between the conductor and the cover.

An insulating washer 24 is ada ted to lit over the block 22 and engage t e bottom casing i6. This Washer ie preferably chamhered as shown at 25 sous t'o provide 'an air pocket for heat insulat' purposes. This Washer separates the heat unit from the bottom ot the receptacle an in addition to providing electric insulation reduces the heat radiation through the bottom.

The parts are assembled by rst placing ,the washer 24 in place on the unit as shown in Fig. 2 and then placing the parte in the bottom Oi the receptacle 11, the latter hav-1 ing its bottom cut away se as to admit the f insulating block. Ihe vessel 10 is then placed within the receptacle and is wedged 1n place by means oi the. bayonet conne'cs tions. rille unit is thus forced into geod heat-conducting relation with the bottom. of the vessel so as to make e. thoroughly' eflicient heat-conducting joint. The circuit connections Will be made in the usual way by means of a connector fitting over the terminals 20 and 21. If the heating unit is destroyed from any cause, it may be replaced by simply separating the receptacle and vessel and Insertm a new unit.

It will be seen that I ave provided a ver simple and efficient heater, the 'parts of Whio are renewable by unskilled hands.

What I regard as a very important feature of my invention is the self-contained unit having an insulating terminal block secured thereto so that the unit as a Whole may be easil removed and replaced by unskilled han s.

While I have shown my invention es applied to a specic form of heater, the

parts being arranged in a deiinite-Way, it

should be understood that I do not limit my invention in any of these particulars exec t in so lfar as it is limited by the scope of t ie claims annexed hereto.

What I claim as new and desire to secure by Letters Patent of the United States, is,- 1. An electric heater comprising a receptacle, a container arranged to enter the same, a flat self-contained unit l etwcen said ftacle, a heating unit mounted therein, a

container arranged to enter said receptacle, and engage the heating unit, and means for locking said receptacle and container together to force the unit into intimate thermal relation with the container.

4. An electric heater comprising a flat heating unit, a receptacle for supporting the same, a container arranged to enter said receptacle to engage the tlat surface of said unit, means for wedging said receptacle and container to ether, and aconnecting terminal secured to said unit and projecting through the bottom of said receptacle.

5. An electric heater comprising a body portion, a self-contained heating unit, a support for said unit, and means for locking the support to the body portion to secure the unit rigidly between said parts.

6. An electric heater comprising a body portion, a itat heating unit therefor, a receptacle for supporting said unit arranged to be wedged to said body portion and hold the flat surface of said unit in intimate thermal relation therewith, and a connecting terminal secured to said unit and projecting through the bottom of said receptacle.

7. An electric heater comprising a body portion, a flat heating unit theref'or, a receptacle for supporting said unit in heatconductive relation to said body portion, and means for locking said body portion and receptacle together.

8. An electric heater comprising a body portion, a flat heating unit therefor, a receptacle for supporting said unit in heatconductive relation to said body portion, a connecting terminal secured to said unit and projecting through said receptacle, and

jecting through one of said casings, ane

9. An electric heating unit comprising a 6 resistance conductor, telcscoping caslngs inclosing the same, and a connecting plug rigidly secured to one of said casings.

10. An electric heating unit comprising a resistance (-.onduct-or, telest-.oping casings inclosing the same, connecting terminals )rol an insulating plug molded about said terminals. 1t. An electric heating unit comprising a resistance conductor, telcscoping casings iuclosing the same, detachable connecting terminals projecting centrally through one ofV said easings, and an insulating plug molded about said terminals.

'12. A self-contained heating unit eemprising a resistance conductor, teleseoping Vcasings int-.losing the same, a projecting member rigidly secured to one ol' said casings havingconnecting terminals embedded therein and projecting thm'efrom, and electrical connections between the conductor and said terminals.

13. A self-contained waterproof electric heating unit vcomprising a resistance conductor protectively inclosod in heat-resisting telescopin'g casings and having as an integral element a projecting member with connecting terminals embedded therein and projecting therefrom, said terminals projecting inward through the casing to form connections for the conductor. f

14. An electric heating unit comprising a flat resistance element., a casing entirely inclosing the same,` and a connecting plug secured to said casing.

15'. An electric heating unit comprising a llat resistance element, a casing entirely inclosing the same, a connecting plug extending from said casing perpendicular to the plane thereof, and terminals projecting from the plug parallel with the casing.

16. An electric heating unit comprising a resistance conductor distributed over a flat heating surface and inclosed in a metallic casing, and connecting terminals inclosed in a refractory insulating compound projecting from thecasing and having exposed ends.

In witness whereof, I have hereunto set my hand this 14th day of January, 1908.

WILLIAM S. ANDREWS.

Witnesses:

BENJAMIN B. HULL, HELEN Onronn. 

